The idea there are living organisms, as yet undiscovered by humans, living on other planets, has fascinated people for years. The search for alien life is not just a science fiction topic – it’s part of a scientific field called astrobiology.
Astrobiology is more than looking for aliens. It’s the study of the origin, evolution and future of life in the Universe, including here on Earth. It brings together a number of different scientific fields, including astrophysics, biology, geology and paleontology.
The early Earth where life first evolved was quite different to Earth today. There was no oxygen in the atmosphere at the time, just volcanic gases. Exactly how the first simple organisms came to exist in this hostile environment is still unknown. The hope is that similar environments can be located in the Universe to shed light on the development of life on Earth.
One of the biggest challenges of astrobiology is distance. It’s just not possible to send human researchers across the vast distances of space to other planets in our Solar System, let alone planets around other stars.
The data available to astrobiologists has increased as remote sensing technology has improved. Using telescopes based on Earth to analyse stars and planets makes it possible to draw conclusions about the potential for life outside Earth. For example, astronomers may be able to tell if a planet is made of gas or rock to help determine if it could support life.
The Square Kilometre Array (SKA) will be the world’s largest radio telescope. While its purpose is not for astrobiology, it could support astrobiological research. For example, to understand how life might form on a planet, it’s necessary to understand its geology. The SKA could be used to detect the radio wave bursts of a distant planet, revealing information about its magnetic field. Or it could find planets forming in the rings of dust and rock around young stars.
Maybe the SKA could be used to discover radio waves from an advanced alien civilisation. While this is not likely, astrobiologists will continue to look for more clues about how life began, both here on Earth and in the stars.
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